mineral
Purple Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO2)
Hardness: 6.5-7 (Mohs), Color: Deep purple (artificially enhanced), Luster: Vitreous to waxy, Crystal Structure: Hexagonal (trigonal microcrystalline), Specific Gravity: 2.6-2.65
- Hardness
- 6
Identified More mineral →
Explore Purple Chalcedony (likely dyed Agate) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs), Color: Deep purple (artificially enhanced), Luster: Vitreous to waxy, Crystal Structure: Hexagonal (trigonal microcrystalline), Specific Gravity: 2.6-2.65
Formation & geological history
Forms in volcanic and sedimentary rocks as nodules or veins from silica-rich groundwater. Most deep purple chalcedony cabochons in jewelry are created by staining porous natural agate with iron or chromium salts.
Uses & applications
Primarily used in jewelry as cabochons, beads, and ornamental carvings; also popular in spiritual/metaphysical collecting.
Geological facts
Chalcedony is a cryptocrystalline form of silica. While natural purple chalcedony (like 'Grape Agate' or 'Holly Blue') exists, the uniform saturated color and 'orbicular' circular banding visible in this specimen suggest it is a dyed Brazilian agate.
Field identification & locations
Identify by its waxy luster and inability to be scratched by a steel blade. In the field, look for botryoidal (grape-like) textures in volcanic cavities. Commonly found in Brazil, India, and Madagascar.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock
Granite
Granite (Phaneritic intrusive igneous rock)
igneous